1. Field
One or more embodiments of the present invention relate to an image processing apparatus, method and medium, and more particularly, to an image processing apparatus, method and medium which perform interpolation such that a pixel value in each pixel region included in a digital image, and an average value of interpolation data extracted using a predetermined interpolation method in the pixel region are equal.
2. Description of the Related Art
Digital signal processing techniques have gradually replaced analog signal processing techniques. Today, many aspects of our lives are being digitalized, and such digitalization is readily apparent in the field of imaging. For example, analog televisions (TVs) are being replaced by digital TVs, and analog cameras are being replaced by digital cameras. Accordingly, many studies are being conducted on digital image processing, in particular, image interpolation.
Conventional image interpolation techniques include, as examples, a linear interpolation technique, a nearest neighbor interpolation technique, a cubic interpolation technique, and a cubic-spline interpolation technique. In these techniques, all adjacent pixels are regarded as points and are interpolated accordingly.
However, in the case of a digital image, each pixel may be regarded as a region. When a subject is photographed using an image input apparatus such as a digital camera or a scanner, the image input apparatus digitalizes the amount of light collected by a lens using a light-receiving device such as a charge coupled device (CCD), for example. Therefore, each pixel has an average value of brightness in a certain area through the lens. The same is true for a graphic image generated using a computer.
For this reason, when image data is interpolated using a conventional point-based interpolation technique, unintended errors and distortions may occur. One of the major effects of such distortions on the quality of an image is that a restored image may be smoother than a real image. Hence, the restored image may blur.
A digital image processing technology, in particular, a digital image interpolation technology, may be used for image output apparatuses such as TVs and monitors, printing apparatuses such as printers, and image input apparatuses such as cameras and scanners, for example. In addition, the digital image processing technology may be utilized in diverse fields including military, medicine, broadcasting, industry and household appliances. As users become more sophisticated, improved quality becomes increasingly important. Accordingly, an ability to provide faster and higher-quality images has become an important factor in the field of digital image processing.
In this regard, a method of extracting a high-quality interpolated image using given image information, and without requiring significant computation time, is required.